British Journal of Nutrition

Dietary Surveys and Nutritional Epidemiology

Association between dietary phyto-oestrogens and bone density in men and postmenopausal women

Gunter G. C. Kuhnlea1a2a3 c1, Heather A. Warda2, Anna Vogiatzogloua1, Robert N. Lubena2, Angela Mulligana2, Nicholas J. Warehama3, Nita G. Forouhia3 and Kay-Tee Khawa2

a1 Department of Food and Nutritional Sciences, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UK

a2 Strangeways Research Laboratory, Department of Public Health and Primary Care, Institute of Public Health, MRC Centre for Nutritional Epidemiology in Cancer Prevention and Survival (CNC), University of Cambridge, Wort's Causeway, Cambridge CB1 8RN, UK

a3 MRC Epidemiology Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK


Phyto-oestrogens have been associated with a decreased risk for osteoporosis, but results from intervention and observational studies in Western countries have been inconsistent. In the present study, we investigated the association between habitual phyto-oestrogen intake and broadband ultrasound attenuation (BUA) of the calcanaeum as a marker of bone density. We collected 7 d records of diet, medical history and demographic and anthropometric data from participants (aged 45–75 years) in the European Prospective Investigation into Cancer-Norfolk study. Phyto-oestrogen (biochanin A, daidzein, formononetin; genistein, glycitein; matairesinol; secoisolariciresinol; enterolactone; equol) intake was determined using a newly developed food composition database. Bone density was assessed using BUA of the calcanaeum. Associations between bone density and phyto-oestrogen intake were investigated in 2580 postmenopausal women who were not on hormone replacement therapy and 4973 men. Median intake of total phyto-oestrogens was 876 (interquartile range 412) μg/d in postmenopausal women and 1212 (interquartile range 604) μg/d in men. The non-soya isoflavones formononetin and biochanin A were marginally significant or significantly associated with BUA in postmenopausal women (β = 1·2; P < 0·1) and men (β = 1·2; P < 0·05), respectively; enterolignans and equol were positively associated with bone density in postmenopausal women, but this association became non-significant when dietary Ca was added to the model. In the lowest quintile of Ca intake, soya isoflavones were positively associated with bone density in postmenopausal women (β = 1·4; P < 0·1). The present results therefore suggest that non-soya isoflavones are associated with bone density independent of Ca, whereas the association with soya or soya isoflavones is affected by dietary Ca.

(Received September 20 2010)

(Revised February 08 2011)

(Accepted February 09 2011)

(Online publication May 17 2011)


c1 Corresponding author: G. G. C. Kuhnle, fax +44 118 931 0080, email


Abbreviations: BUA, broadband ultrasound attenuation; DINER, Data into Nutrients for Epidemiological Research; EPIC, European Prospective Investigation into Cancer; SWAN, Study of Women's Health Across the Nation